Background of the Invention
a. Field of the Invention
[0001] This invention relates to a test sample color comparison device used in biochemical
examinations such as urine sugar, blood sugar, urobilin and other such examinations.
The color comparison device contains a plurality of color reference shades which are
sequentially compared to a color of a test stick reagent portion which has been impregnated,
for example, with blood, in order to determine which of the color reference shades
best matches the color of the reagent portion. The color shade which best matches
the color of the test paper provides an indication of a biochemical condition, for
example, the amount of sugar in the blood.
b. Discussion of Related Art
[0002] Fig. 3 (perspective view) and Fig. 4 (cross-sectional view) show a color comparison
device on which the present invention improves. Specific details of this device are
disclosed in Japanese Application No. 62-310246 and U.S. application Serial No. 268,561
filed November 8, 1988, the disclosure of Serial No. 268,561 is incorporated herein
by reference.
[0003] Another related color comparison device is also disclosed in U.S. application Serial
No. 224,367 filed July 26, 1988, the disclosure of which is also incorporated herein
by reference.
[0004] The color comparison device of Figs. 3 and 4 comprises a casing unit 1 which includes:
an insertion section in the form of a test stick insertion groove portion 13 for removably
receiving a color test paper portion 51 of a test stick 5: a protruding display section
11 for displaying the results of a color comparison; a manipulable rotatable wheel
2 rotatably fitted on the protruding display section 11 of the casing unit 1; a comparison
color sample section 21 attached to the upper surface of the manipulable wheel 2 and
having a plurality of staged reference color shades arranged in a circular array;
a plurality of converter switches K mounted on the casing unit 1 in registry with
the wheel 2 which convert the results of a visual comparison between the comparison
color sample section 21 and the color test paper portion 51 into electrical signals
representing the color shade on the wheel 2 which best matches the color of the test
paper portion 51; an uneven patterned code section 4 integrally mounted on the underside
of the wheel 2 and having an uneven pattern (defined by thickened portions 41 and
thinned portions 42) corresponding to the staged color shades of the comparison color
sample section 21 so as to operate the converter switches K as wheel 2 rotates; and
a display means 14 (composed of a CPU and other electronic compounds) for displaying
in a display section 17 the significance represented by the color shade which best
matches the test paper portion 51 as designated by the converter switches K.
[0005] When a test sample color comparison is to be carried out using the above color comparison
device, the test stick 5 is inserted into the stick insertion groove portion 13. In
this condition, the color test paper portion 51, passed through a stick insertion
inlet portion 35, is viewed through a comparison window 35 and overlies the comparison
color sample section 21 of wheel 2 in registry therewith. In this condition, the manipulable
wheel 2 is angularly moved (rotated) so that the color of the color test paper portion
51 can be visually compared with the staged color shades on the color sample section
21 as wheel 2 rotates to determine which color shade is the closest to the color of
the test paper portion 51. As the wheel 2 is rotated, the comparison color sample
section 21 underlying the color test paper portion 51 is also rotated as is underlying
uneven patterned code section 4, mounted on the underside of the wheel 2, so that
the plurality of converter switches K underlying the uneven patterned code section
4 in registry therewith are turned on or off in accordance with rotation of wheel
2. As a result, an electrical signal representative of the selected color shade which
underlies the test paper portion 51 at any given time is generated by the converted
switches K so that a signal representing the section color shade which then underlies
and best matches the color of the test paper portion 51 is generated in accordance
with the states (ON or OFF) of the converter switches K. The significance (for example,
the amount of blood sugar) of the selected color shade is displayed in the display
section 17 through a memory means which stores the significance of the color shades
for different angular positions of wheel 2, as determined by the electrical signals
generated by converter switches K.
[0006] In the color comparison device of Figs. 3 and 4, a stick insertion groove portion
13 of predetermined depth is provided in the upper surface of the casing unit 1 at
one end portion thereof at a position centrally of the width of casing unit 1. The
stick insertion groove portion 13 communicates with the comparison window 33, through
which the comparison color sample section 21 can be viewed, through the stick insertion
inlet portion 35 which is provided at one end of a cover unit 3 fitted on the casing
unit 1. The cover unit 3 contains a window 34 for viewing display 17. The bottom surface
of the stick insertion groove portion 13 is flat as shown in Fig. 4 lies flush with
the upper surface of the comparison color sample section 21. Therefore, when the test
stick 5 is inserted into the stick insertion groove portion 13, with the color test
paper portion 51 provided at the leading end portion, the leading end passes through
inlet portion 35 and becomes vertically registered with the comparison window 33;
that is, the color test paper portion 51 is disposed over the upper surface of the
comparison color sample section 21, and the test stick 5 is disposed horizontally.
[0007] In this inserted condition of the test stick 5, it is disposed horizontally in a
space between the cover unit 3 and the comparison color sample section 21, but it
is not held or fixed to the display device. It has been found that this arrangement
may suffer from disadvantages in use, one such disadvantage being that if the casing
unit 1 is tilted during the color comparison operation, the test stick 5 can be accidentally
disengaged from the casing unit 1.
Summary of the Invention
[0008] It is therefore an object of this invention to provide a color comparison device
which overcomes the above difficulty and can be handled more conveniently without
suffering from an accidental disengagement of a test stick from a casing unit.
[0009] This object has been achieved by a color comparison device comprising a casing unit
having a comparison window for displaying a rotatable comparison color sample section,
a display window for displaying the results of the color comparison; a test stick
insertion groove portion formed in an upper surface of the casing unit at one end
portion thereof and disposed generally centrally of the width of the casing unit,
with the insertion groove portion communicating with the comparison window, and with
the stick insertion groove portion having a bulged fixing section by which a test
stick when inserted in the insertion groove portion is inserted in a flexed condition
so that it is held by its flexure in the insertion groove and to the display device.
[0010] In this color comparison device, the stick insertion groove portion communicates
with the comparison window through a stick insertion inlet portion which is provided
at one end of a cover unit fitted on the casing unit and having the display window
and the comparison window. The stick insertion groove portion has the bulged fixing
section at its proximal and from which the test stick is to be introduced into this
groove portion. By virtue of the provision of this bulged section, the stick insertion
groove portion is the highest at the proximal end. With this arrangement, the peak
of the bulged section is at a level considerably higher than the upper surface of
the comparison color sample section. Therefore, when the test is to be inserted into
the stick insertion groove portion, the test stick is inserted in an inclined condition
because of the provision of the bulged section at the proximal end of this groove
portion, and the distal end portion of the test stick is passed through the stick
insertion inlet portion, so that the color test paper portion of the test stick is
brought into registry with the comparison window. When the distal end of the test
stick is inserted into the stick insertion inlet portion, the test stick is urged
downwardly, so that the test stick is flexed.
[0011] The test stick is usually made of a sheet of a plastics material, and therefore the
test stick, when flexed, produces a restoring force. This restoring force is borne
at two points, one is the peak of the bulged section and the other is the stick insertion
inlet portion, and the test stick is fixed in a flexed condition. Therefore, the test
stick in its inserted and flexed condition will not be accidentally disengaged from
the device body even when the body is held or positioned in different orientations,
thus providing for a more convenient use.
Brief Description of the Drawings
[0012] The above objects advantages and features of the invention will be better understood
from the following detailed description provided with the preference to the accompanying
drawings in which:
Fig. 1 is a cross-sectional view of a color comparison device embodying the present
invention;
Fig. 2 is a perspective view of the color comparison device;
Fig. 3 is a perspective view of a color comparison device upon which the present invention
improves; and
Fig. 4 is a cross-sectional view of the device of Fig. 3.
Detailed Description of the Invention
[0013] Fig. 2 is a perspective view of a preferred embodiment of a color comparison device
of the present invention, and Fig. 1 is a cross-sectional view thereof.
[0014] This color comparison device is generally similar in construction to the color comparison
device shown in Figs. 3 and 4 and similar parts are designated by the same reference
numbers. More specifically, the color comparison device of the invention comprises
a casing unit 1 which includes an insertion section (stick insertion groove portion)
13 for removably receiving a color test paper portion 51 of a test stick 5, and a
protruding display section 11 for displaying the results of the color comparison.
A manipulable wheel 2 is rotatably fitted on the protruding display section 11 of
the casing unit and a comparison color sample section 21 is attached to the upper
surface of the manipulable wheel 2 and has a plurality of staged reference color shades
arranged in a circular array. A plurality of converter switches K are mounted on the
casing unit 1 in registry with the wheel 2 so as to convert into results of a visual
comparison, as wheel 2 is rotated, of the comparison color sample section 21 which
best matches the color test paper portion 51 into electrical signals.
[0015] An uneven patterned code section 4 is integrally mounted on the underside of the
wheel 2 and has an uneven pattern (defined by thickened portions 41 and thinned portions
42) corresponding to the staged color shades of the comparison color sample section
21 so as to operate the converter switches K. A display means 14 (composed of a CPU,
memory and other electronic components) is also provided for displaying in a display
section 17 the significance represented by the color shade then underlying the test
paper portion 51, as designated by the converter switches K.
[0016] The display means determines, using a central processing unit (CPU), which color
shade is in registry with the test paper portion 51 by the electrical signals generated
by converter switches K and uses the electrical signals to retrieve from a memory
a display value corresponding thereto which represents a biochemical condition, e.g.,
the amount of sugar in the blood. This value is then displayed to an operator.
[0017] A feature of the present invention resides in the fact that a bulged fixing section
6 is formed on the stick insertion groove position 13 provided at one end of the casing
unit 1 by which bulged section the test stick 5 is inserted in the stick insertion
groove portion 13 in a flexed condition.
[0018] As seen from Fig. 2 which is the cross-sectional view, the casing unit 1 comprises
a hollow body of a flat rectangular shape housing an electronic circuitry position
14 comprising a power source, the CPU, the memory, etc., the casing unit 1 having
the protruding display section 11 at a central portion of the upper surface thereof
and also having a protruding platform 12 at one end portion thereof. The stick insertion
groove portion 13 is defined by a recess formed in the upper surface of the protruding
platform 12 and extending centrally of the width thereof. The cover unit 3 is fitted
on the upper portion of the casing unit 1, and has a flat section 31 which has a manipulable
display window 34 formed therethrough and disposed in registry with the protruding
display section 11, and a comparison window 33 formed through the flat section 31
and disposed in registry with the comparison color sample section 21. A stick insertion
inlet portion 35 defined by a recess is provided at insertion groove portion 13. The
stick insertion groove portion 13 communicates with the comparison window 33 through
the stick insertion inlet portion 35. The test stick 5 is inserted into the stick
insertion groove portion 13 to reach the comparison window 33 through the stick insertion
inlet portion 35. In this inserted condition, the leading or distal end portion of
the test stick 5 is disposed in a space formed between the cover unit 3 (i.e., the
upper wall of the insertion inlet portion 35) and the upper surface of the comparison
color sample section 21.
[0019] The stick insertion groove portion 13 has the bulged section (bulged fixing section
) 6 at its inlet side or proximal end portion from which the test stick 5 is to be
introduced into the groove portion 13, the bulged section 6 being upwardly curved.
Because of the provision of the bulged section 6, the stick insertion groove portion
13 is the highest at its inlet side and gradually slants downwardly toward the stick
insertion inlet portion 35. That portion of the insertion groove portion 13 extending
from the stick insertion inlet portion 35 to the comparison color sample section 21
is flat (horizontal), as is the case with the conventional stick insertion groove
portion of the device shown in Figs. 3 and 4.
[0020] The cover unit 3 has a stopper projection 37 formed on the lower surface thereof
adjacent to a rear end of the comparison window 33 remote from the stick insertion
inlet portion 34, and a receptive portion 19 in the form of a recess for receiving
the stopper projection 37 is formed in the upper surface of the casing unit 1. Thus,
the stopper projection 37 fitted in the receptive portion 19 limits a depth or length
of insertion of the test stick 5 between the cover unit 3 (the comparison window 33)
and the casing unit 1 (the comparison color sample section 21). In other words, the
stopper projection 37 is so positioned that the color test paper portion 51 of the
inserted test stick 5 can be located in vertical registry with the color comparison
sample section 21.
[0021] When a test sample color comparison is to be carried out using the color comparison
device of the above construction, a mode key 1a, exposed through the manipulable window
34, is first depressed to turn on the power source. Then, a specimen, for example,
blood is applied to the test paper portion 51 of the test stick 5, and then a start
key 1b is depressed to activate a timer which sets a predetermined reaction time (i.e.,
time required for the color reaction on test paper portion 51). When the timer stops
its operation and the operator is notified by, for example, an audible beep, the test
stick 5 is inserted into the stick insertion groove portion 13, with its test paper
portion 51 first introduced thereinto. At this time, the test stick 5 is moved into
the stick insertion inlet portion 34 in an inclined condition because of the provision
of the bulged section 6. Therefore, the test stick 5 is flexed to produce a restoring
force, and this restoring force is borne by the apex or peak of the bulged section
6 and the insertion inlet portion 35. The distal end of the test stick 5 is passed
through the insertion inlet portion 35 while it is kept in the flexed condition, so
that the distal end is brought into abutment against the stopper projection 37, thereby
preventing a further advance of the test stick 5. In this condition, the color test
paper portion 51 is exposed and viewed through the comparison window 33, and is disposed
in proper registry and contact with the upper surface of the comparison color sample
section 21. It is also held in position by its flexure.
[0022] Thus, the test stick 5 is passed through the insertion inlet portion 35 in the flexed
condition because of the provision of the bulged section 6, and the restoring force
produced by this flexing (i.e., a restoring force of the material of the test stick
5) is borne by the insertion inlet portion 35 so that the test stick is fixed. Therefore,
even if the device body 1 is tilted during the time when the manipulable wheel 2 is
rotated to bring different color shades on wheel 2 into registration with test paper
portion 51, the test stick will not be accidentally disengaged from the device body,
thereby ensuring a stable color comparison operation.
[0023] As described above, in the present invention, the stick insertion groove portion
is provided with the stick-fixing bulged section, and therefore the test stick is
moved into the stick insertion inlet portion in an inclined condition due to the bulged
section, so that the test stick is flexed. This flexed condition is maintained by
the bulged section and the insertion inlet portion to thereby positively fix the test
stick. Therefore, the test stick in its inserted condition is firmly fixed, and so
long as an outward pulling force is not applied to the test stick, the test stick
will not be accidentally disengaged from the device body during the color comparison
operation.
[0024] While a preferred embodiment of the invention has been described and illustrated
it should be apparent that many modifications can be made without departing from the
spirit and scope of the invention. Accordingly, the invention is not limited by the
foregoing description but is only limited by the scope of the appended claims.